As indicated above, the researchers who conducted this phase I study also conducted two phase II studies. The phase II studies tested the ability of NDV oncolysates to delay the progression of melanoma from regional cancer to systemic disease.[1,2,4,11] The patients in these phase II studies had undergone surgery to remove the primary cancer and the radical lymph node dissection because of the presence of palpable disease in regional lymph nodes.
The first phase II study involved 32 patients, 5 of whom had been treated previously with other types of immunotherapy.[1,2,4,11] Melanoma was detected in 1 to 3 regional lymph nodes in 84% of the patients, in 4 to 5 regional lymph nodes in 9% of the patients, and in 6 to 8 regional lymph nodes in 6% of the patients. The second phase II study was initiated 4 years after the start of the first one, and it involved 51 additional patients.[1,2,11] Among these latter patients, 66% had melanoma detected in 1 to 3 regional lymph nodes, 16% had melanoma detected in 4 to 5 regional lymph nodes, and 18% had melanoma detected in 6 or more regional lymph nodes.[1,2,11]
In both studies, the patients were given subcutaneous injections of NDV oncolysates once a week for 4 weeks, beginning 4 to 8 weeks after surgery, followed by more subcutaneous injections given every 2 weeks until 1 year after surgery, and then continued subcutaneous injections given at intervals that increased gradually to every 3 months over the course of a 5-year period. From years 5 through 15 after surgery, some patients received additional oncolysate injections, which were given at intervals varying in length from 3 months to 6 months. Four of the patients in the first study were treated with both autologous and allogeneic vaccines, whereas the remaining patients in that study and all of the patients in the second study were treated with allogeneic vaccines only. Five years after surgery, 72% of the patients in the first study and 63% of the patients in the second study were reported to be alive and free of detectable melanoma. The corresponding survival value for historical control subjects who had palpable regional disease was approximately 17% (a value derived from the scientific literature). Ten years after surgery, 69% of the patients in the first study and 59% of the patients in the second study were reported to be alive and free of detectable melanoma, compared with survival values of 5% to 15% for historical control subjects who had palpable regional disease or 33% for historical control subjects who had either palpable regional disease or microscopic evidence of regional lymph node metastasis.[1,2] Fifteen years after surgery, overall survival values of 59% and 53% were reported for patients in the first and second studies, respectively, with one survivor in the first study experiencing metastatic disease. In general, survival in these two studies did not seem to be influenced by the number of regional lymph nodes that were positive for cancer at the time of radical lymph node dissection, and the patients who received both autologous and allogeneic vaccines did not appear to fare any better than the patients who received allogeneic vaccines only.